src/base/mmap.h

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#ifndef MOZC_BASE_MMAP_H_
#define MOZC_BASE_MMAP_H_

#ifdef MOZC_USE_PEPPER_FILE_IO
#include <memory>
#endif  // MOZC_USE_PEPPER_FILE_IO
#include <string>

#include "base/port.h"

namespace mozc {
class Mmap {
 public:
  Mmap();
  ~Mmap() {
    Close();
  }
  bool Open(const char *filename, const char *mode = "r");
  void Close();

#ifndef MOZC_USE_PEPPER_FILE_IO
  char &operator[](size_t n) { return *(text_ + n); }
  char operator[](size_t n) const { return *(text_ + n); }
  char *begin() { return text_; }
  const char *begin() const { return text_; }
  char *end() { return text_ + size_; }
  const char *end() const { return text_ + size_; }
#else  // MOZC_USE_PEPPER_FILE_IO
  char &operator[](size_t n) { return *(text_.get() + n); }
  char operator[](size_t n) const { return *(text_.get() + n); }
  char *begin() { return text_.get(); }
  const char *begin() const { return text_.get(); }
  char *end() { return text_.get() + size_; }
  const char *end() const { return text_.get() + size_; }
#endif  // MOZC_USE_PEPPER_FILE_IO

  size_t size() const { return size_; }

#ifdef MOZC_USE_PEPPER_FILE_IO
  // Save the data in memory to the file.
  bool SyncToFile();
#endif  // MOZC_USE_PEPPER_FILE_IO

 private:
#ifndef MOZC_USE_PEPPER_FILE_IO
  char *text_;
#else  // MOZC_USE_PEPPER_FILE_IO
  string filename_;
  std::unique_ptr<char[]> text_;
  bool write_mode_;
#endif  // MOZC_USE_PEPPER_FILE_IO
  size_t size_;

  DISALLOW_COPY_AND_ASSIGN(Mmap);
};
}  // namespace mozc

#endif  // MOZC_BASE_MMAP_H_